Improvement invariable exhausts for locomotives



, E. R. ADDISON.if

Variable Exhaust for Locomotives No. 213,311 Patented Mar. 18,1879.

N,FETEHS. PHDTO-UTHOGRAPMER, wAsHxNGToN. d C.

NIIED'TATES PATENT FFICE.

EDWIN R. ADDISON, CF CINCINNATI, OHIO.

IMPROVEMENT IN VARIABLE EXHAUSTS FOR LOCOMOTIVES.

Specification forming part of Letters Patent No. 213,3ll, dated March18, 1879; application iiled August 15, 1878.

To all whom it may concern.-

Be it known that I, EDWIN R. ADDISON, ot Cincinnati, in the county ofHamilton and State of Ohio, have invented certain new and usefulImprovements in Variable Exhausts for Locomotive-Engines, ot' which thefollow-` ing is a specification:

The object of my invention is to provide an exhaust-passage readilyvariable in capacity, and providing a free and smooth delivery in allconditions of its adjustment 3 also, one that will be effective in use,durable, and not liable to get out of order.

rIhe casing of the variableexhaust-nozzle is made in two parts, to admitof adjustment in case ot' wear from use. Within this are a pair ofcurved valves or leaves working on trunnions, and made ,to approach orrecede from each other by means of cams yoked to their concave backs andoperated through the medium of pinions on their journals by a slidingrack having two sets of teeth engaging with the said pinions in such amanner that when the rack is moved in one direction a simultaneousmovement will be imparted to the valves, causing them to approach eachother, and when it is moved in the other direction they will be made torecede from each other.

In order that my invention may be more fully understood, I will proceedto describe it with reference to the accompanying drawings, in'whieh-Figure l is a front View, partlyr in section. Fig. 2 is a rear view withone-half of the casing removed. Fig. 3 is a horizontal section on theline 3 3, Figs. l and 2.

A. A are the two parts of the divided cas ing, within which are a pairof convexfaced valves or leaves, B B, working on trunnions b Z1 at theirlower ends, and operated by cams C C, which occupy the cavities in thehollow backs of the valves, and are encircled by yokes D D, attach ed tothe valves B B, so as to cause the said cams, by their rotation, to movethe valves toward and away from each other. On the front journals of thecams C C are keyed pinions E E.

The simultaneous rotation of the two cams to produce the requiredconcurrent movement of the valves is imparted by a double rack, F, madein the form of a cap, covering the pinions E E, and adapted to slidehorizontally to the right and left across the face of the casing.

The rack-cap F being provided with two ranges of teeth, f and f', theone engaging with the lower side ot' one of the pinions E, and the otherengaging with the upper side of the otherA pinion, it will be apparentthat a' motion ot the rackeap in one direction will turn the two pinionsin opposite directions in such a way as to throw the cams over againstthe backs ot' the valves and cause them to approach each other, and thatthe reverse move'- ment of the rack-cap will move the respective pinionsin the other direction, causing the cams C C to press against the yokesD D, thereby drawing the valves apart and increas ing the capacity oftheport or nozzle. I

In practice the cams C are fitted to the back of the valves B and withinthe yokes D in such a manner as to avoid any lost motion and admit ofsetting the valves accurately at any required proximity or distanceasunder, so as to regulate the capacity ot" the opening with precisionby the movement of the rack-cap F.

It will also be apparent that the convex curvature of the valve-facesgives a better and smoother discharge to the steam, avoiding anyobstruction to the current or draft produced by the exhaust, and thatthe manner of mounting the valves on trunnions and forming their bottomand top ends to t the casing all the way across, and providing, theirupper ends with ian ges t' projecting backward into suitable recesses,eft'ectually excludes dirt from the working parts, as well as increasingthe wearingsurface and the consequent durability of the device.

The making ofthe case A A in two parts adapts it to be adjusted or setup to compensate for wear.

The rack-cap is held in place and guided by spring-plates G Gr, held bythe same screw bolts H H which hold the casing together.

The movement ot' the said rack-cap to reguA late the exhaust may beeffected, as desired, either by a connection with the reversing-leverofthe engine or by a separate connection un= der control of theengineer.

Having thus described my invention, the following is what I claim as newtherein and desire to secureby Letters Patent:

l.V The exhaust-nozzle casing, made in two equal or similar parts, A A',coupled by bolts H H, and containing` valves B B to regulate thecapacity of the nozzle, the whole being` constructed substantially asherein shown and described. Y

2. The valves B B, constructed With vertically convex faces and concavebacks, and Working Within the casing A A in the Inanner and for thepurpose set forth.

3. The combination, in a variable exhaust, of the valves B B, cams G C,and `Vokes D D, constructed and operating substantially as and for thepurposes set forth.

4. The rack-cap F ff', constructed substantially as described, andacting' on pinions E E on the journals of the cams C G, as explained.

5. The combination ofthe casing` A A', valves B B, cams C C, yokes D D,pinions EE, rackcap Fff, spring guideplates Gr G, and bolts H H, as andfor the purposes set forth.

E. It. ADDISON.

Witnesses:

A. H. DIXON, GEO. H. HIGH.

